Dynamo-electric machine.



l. W. BURLEIGH.

DYNAMO ELECTRIC MACHINE.

APPLICATION FILED IuLY9. |909.

Patented June 13, 1916.

JOHN WESLEY BURI1EIGH,`OF ROWBARTON, TAUN'ION, ENGLAND.

DYNAMIC-ELECTRIC MACHINE.

Specification of Letters Patent.

Patented Juno 13, 1916.

Application filed July 9, 1909. Serial No. 506,807.

To all whom t may concern Be it known that I. J'onN lVnsLnr Bun- LEIGH,of Hazeldene, Leslie street, Rowbart0n, Taunton, Sol'nersetshire,England, have invented new and useful Improvements in Dynamo-ElectricMachines, of which the following is a specification.

My invention relates to improvements in dynamo-electric machines, and itconsists in the application of commutating poles t0 a known main magnetstructure, namely a magnet structure of the parallel limbed horse-shoetype.

By means of my invention a greater output can be obtained from a givenquantity of material than has hitherto been found possible withcommutating pole machines.

In order that my invention may be readily understood I shall now proceedto describe it with reference to the accompanying drawings whichillustrate a four-pole machine constructed in accordance with myinvention.

In these drawings, Figure I is a cross section taken on the line 1f-a ofFig. II (the armature being indicated by a circle merely), showing thefield coils in position, Fig. II a side view of the carcass showing theVentilating holes and parts of the field coils, and Fig. III a diagramof an arma ture winding in conjunction with the field coils andcommutating poles.

Referring now to these figures, 1, 1 are parallel limbed horse-shoefield magnets united by the yokes 2 each of which carries onecommutating pole 13. On the limbs 3, f1, 5 and 6 of the horse-shoe fieldmagnets (3 and 5 being let us say S poles and 4 and 6 N poles) aremounted the main field coils 7 8, 9 and 10. As will be seen the mainfield coils are arranged so that a part 11 of each lies in the neutralzone directly over and parallel, or nearly parallel, with the coils ofthe armature which at the time are undergoing commutation. The oppositeparts 19. of the main field coils are placed as shown so as to leave aconsiderable space between them. In this space commutating or reversingpoles 13 are placed with their coils 14 the said poles being carried bythe yokes 2 connecting the main horse-shoe magnets. The arrangement ofpoles and windings is shown diagrammatically in Fig. III in which thefull line 15 represents a winding of a series wound armature, the dottedline 16 the portions 11 of the field coils and the rectangles 17 thecommutating poles. By locating the field coils m this position I findthat they so assist in the com1nutationthat the flux required from eachcommutating pole is only about half' of that required in the known typeof connnutating pole machine having one commutating pole per pair ofmain poles. In other words the effect derived from placing portions ofthe main coils in the position mentioned is such that the excitationrequired on each commutating pole is little, if any, in excess of anordinary machine having one commutating pole per main pole. And,further, by placing portions of the field coils in the positionsmentioned magnetic leakage is reduced.

A great advantage obtained by my arrangement of the axes as just definedis that the path for the main flux due to the main field coils whichpasses through the horseshoe main magnet frame is of very low inductiondue to the fact that the path zu is only about one-third of the path y.

Owing to the small magnetic fiux in the yokes 2 these may be of smallcross-sectional area and thus large Ventilating holes may be cut at 18through which air may pass for cooling purposes. Thus in a machineconstructed under my invention a much larger percentage of heat may beremoved than in the case of a machine of the usual protected type ofpresent day construction.

Any of the usual windings may be employed both for the field and thearmature coils.

In the term dynamo-electric machine it will be understood that I includegenerators, motors, dynamotors, and the like.

It is to be understood that I do not limit myself to the number of polesshown in the drawings as any convenient number of poles may be employed.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is 1. A dynamo electric machine having a fieldmagnet frame, comprising a series of pairs of horse-shoe main fieldmagnets joined by a frame yoke portion of reduced cross-section, andcarrying interpole cores, exciting windings for the main field cores andexciting windings for the interpole cores.

2. A dynamo electric machine having main-poles with their coresparallel, a yoke of ymagnetic material of less cross-section than thepath for the niain flux and a coinniutatingpole Carried thereby. anarmature, lield-eoils arranged with those portions which lie in theneutral Zone elose to, innnediatelyv over and parallel or nearlyvparallel with the coils olf said armature undergoing eounnutation, andwith those portions remote .troni the neutral Zone spaced troni theeoniniutating pole.

3. l de rnaiuo-eleetrie niaehine having` two oppositely disposedparallel-linibed horseshoe main magnet struetures, jfolies ot niagnetiematerial @onine-ting said inain inagnets, eonuuutati11g-poles carriedone by each ol said .rolces and disposed substantiall;7 norinal to theliinbg ot said magnetiA an armature, and held-coils arranged with thoseportions which lie in the neutral zone close to. innnediatel)v orer andparallel or nearly parallel with the coils oi" said armature undergoingcommutation, and with those portions remote troni the neutral Zonesspaced from the eonnnutating` poles, thereb7 providing a comparativelylarge space between theni for the said interposed eonnnutatingpoles.`respeetirely7 substantially as described.

ln Witness whereof l hare signed niy naine to this speeilieation in thepresence of two subseribing witness JUllil lVlCSLEY BURLEIGH.

Witnesses:

Vlinznan'r Gnonon .Diimvnx'r Veena, Cininnns Hifznnr DENMAN.

Copies this patent may be obtained for five cent-s each, by addressingthe Commissioner of '.Patcnts,

Washington, D. C.

